CanvasImageSource is a helper type representing any objects of one of the following types: HTMLImageElement, HTMLVideoElement, HTMLCanvasElement, or ImageBitmap.
RenderingContext is a helper type representing any of the following rendering contexts CanvasRenderingContext2D, WebGLRenderingContext or WebGL2RenderingContext (which inherits from WebGLRenderingContext).
The WindowBase64 helper contains utility methods to convert data to and from base64, a binary-to-text encoding scheme. For example it is used in data URIs.